Secondary DMEK following failed primary DMEK

Trends and Surgeon Variations in Early Regrafts After Endothelial Keratoplasty: Analysis of the National Medicare Data Set

PURPOSE

The aims of this study were to determine national-level trends in early regraft rates and examine patient-level and surgeon-level characteristics associated with early regrafts.

METHODS

This was a retrospective, cohort study. We identified beneficiaries aged 65 years or older in the 2011 to 2020 Medicare carrier claims data set who underwent Endothelial keratoplasty (EK) and subsequently underwent an early regraft. The incidence of early regraft for each year was calculated and patient-level and surgeon-level characteristics associated with regrafts were examined using a multivariable regression model.

RESULTS

Of 114,383 EK procedures, 4119 (3.60%) were followed by an early regraft, with no significant variations in the rates between years ( P = 0.59). Factors associated with higher odds of early regraft were Black compared with White race (OR 1.151; 95% confidence interval (CI) 1.018-1.302) and the highest quartile of income versus the lowest quartile (OR 1.120; 95% CI 1.002-1.252). Factors associated with lower odds were female sex (OR 0.889; 95% CI 0.840-0.942), receiving surgery in a hospital-based outpatient department versus an ambulatory center (OR 0.813; 95% CI 0.740-0.894), and having a surgeon with the highest quartile of annual EK volume versus the lowest (OR 0.726; 95% CI 0.545-0.967). Early regraft rates among surgeons ranged from 0% to 58.8% with a median [interquartile range] of 3.13 [0-6.15].

CONCLUSIONS

We found no significant increases in the early regraft rates over the past decade in the United States. Patient male sex and Black race, ambulatory surgery center-based location of the surgery, and low surgeon EK volume were associated with early regrafts. Substantial surgeon variability in regraft rates may indicate opportunities for improvement through development of best practices on perioperative management and patient counseling.

Risk Factors for Descemet Membrane Endothelial Keratoplasty Rejection: Current Perspectives- Systematic Review

Descemet membrane endothelial keratoplasty (DMEK) is a corneal endothelial transplantation procedure with selective removal of a patient's defective Descemet membrane and endothelium. It is replaced with a healthy donor Descemet membrane and endothelium without a stromal component. Corneal graft rejection can be at the level of epithelium, stroma as well endothelium. DMEK graft rejection is relatively less common than rejection with DSAEK or penetrating keratoplasty, and a good outcome may be achieved with prompt management. The clinical picture of DMEK rejection is usually similar to endothelial rejection in Descemet Stripping Endothelial Keratoplasty (DSEK/DSAEK), which generally manifests as pain, redness, reduction in visual acuity, stromal edema, endothelial rejection line, keratic precipitates at the back of the cornea and corneal neovascularization. However, more subtle forms of rejection or immune reactions are more common in DMEK compared to DSAEK eyes. Early clinical diagnosis, prompt intervention, and meticulous management safeguard visual acuity and graft survival in these cases. Intensive topical steroids form the mainstay in the management of DMEK rejection. Sometimes, oral or intravenous steroids or other systemic immunomodulators may be required. DMEK graft failure can be primary or secondary, and failure usually requires a second procedure in the form of repeat DMEK or DSEK or penetrating keratoplasty (PKP). A detailed literature search was performed using search engines such as Google Scholar, PubMed, and Google books, and a comprehensive review on DMEK rejection was found to be lacking. This review is a comprehensive update on the risk factors, pathophysiology, primary and secondary graft failure, recent advances in diagnosis, prevention of rejection, and updates in the management of DMEK rejection. The review also discusses the differential diagnosis of DMEK failure and rejection, prognosis, and future perspectives considering DMEK failure and rejection.

Graft Failure after PKP and DMEK: What is the Best Option?

Corneal transplantation is the most commonly performed human tissue transplantation procedure worldwide. Due to the large number of grafts, corneal graft failure has become one of the most common indications for corneal transplantation for immunological and non-immunological reasons (e.g. recurrence of underlying disease, high intraocular pressure, grafted guttae, transmitted HSV or CMV infection). The relatively recently developed lamellar grafting techniques have introduced certain potential complications that may lead to graft failure and require approaches other than penetrating keratoplasty for re-grafting. On the other hand, these new lamellar techniques also offer new possibilities for salvaging failed penetrating grafts, with potential advantages over successive penetrating keratoplasties, such as lower intraoperative risks, faster visual rehabilitation and reduced risk of immune reaction. Today, the patient with good healing who is satisfied with his graft before endothelial decompensation, with low astigmatism and no stromal scars, represents the optimal condition for DMEK after PKP. This can also be combined with phacoemulsification (so-called triple DMEK). Otherwise, a penetrating re-keratoplasty with a larger graft (typically excimer laser repeat PKP 8.5/8.6 mm) is performed to treat edema, scars and irregular astigmatism simultaneously. The medical history carries weight in this decision! Re-DMEK in case of graft failure after DMEK and DSAEK does not require any modification of the standard technique and leads to good visual acuity results if performed quickly. If there is clear stromal scarring after multiple (external) DMEKs, PKP can also be considered to rectify the situation. Otherwise causeless recurrent graft failures must suggest herpetic or CMV endotheliitis and, after PCR analysis of the aqueous humour aspirate, be treated appropriately with medication.